A school bus, typically painted an iconic yellow colour, is a multi-purpose vehicle used primarily for transporting children to and from school.
During the Mist phenomenon, a school bus was used to apparently evacuate school children from the area. Unfortunately, it was caught in the Mist before it could escape and was apparently attacked by Gray Widowers, as it was covered in webbing with its doors open. When David Drayton and his group passed by in David's Land Cruiser, they shone lights inside the bus, revealing the cocooned corpse of a little girl. The bus's other occupants, if any, were nowhere to be seen, so it is unknown if they escaped or were killed and dragged off.